It is known to introduce endovascular stent grafts into the vasculature of a patient to bridge an aneurism or damaged portion of the wall of the vasculature. Problems can occur, however, where the damage to the vasculature includes or is adjacent to a branch vessel from a main artery because occlusion of the branch vessel may cause permanent damage to the patient.
Examples of such branch vessels are the renal and the mesenteric arteries extending from the aorta.
Fenestrations in a stent graft have been proposed to allow access to the branch vessel from a main stent graft but it is often necessary to provide a side branch graft to maintain access into the branch vessel. Catheterisation of such a branch vessel from a delivery device through the fenestration enables deployment of a covered stent or uncovered stent into the side vessel. This invention provides an improved apparatus for catheterisation and deployment of side branch grafts.
Throughout this specification the term distal with respect to a portion of the aorta, a delivery device or a prosthesis means the end of the aorta, delivery device or prosthesis further away in the direction of blood flow away from the heart and the term proximal means the portion of the aorta, delivery device or end of the prosthesis nearer to the heart. When applied to other vessels similar terms such as caudal and cranial should be understood.
Throughout this discussion the term “stent graft” is intended to mean a device which has a tubular body of biocompatible graft material and at least one stent fastened to the tubular body to define a lumen through the stent graft. The stent graft may be bifurcated and have fenestrations, side arms or the like. Other arrangements of stent grafts are also within the scope of the invention.2.